Fe2O3 nanoparticles, of which sizes vary from 4 to 40nm, were introduced into polypyrrole(PPy) films while pyrrole monomers were electrodeposited onto ITO electrodes. When measured in surface photovoltage spectroscopy(SPS), new photovoltaic behaviors were observed in both cases containing small and large Fe2O3 particles. in terms of band structure and polaron theory, together with the reference of absorption spectra, some principles involved were revealed.